Device for fastening panel-form mats

ABSTRACT

The invention relates to a device for fastening panel-form mats, in particular flexible photovoltaic solar panels, to a supporting structure, having at least one clamping clip ( 10 ) in the shape of a section of a profiled body made of plastics material having opposing profiled limbs ( 12, 14 ), which form a clamping space ( 18 ) therebetween for a holding region ( 8 ) of the relevant mat received therein. In the clamping space the profiled limbs ( 12, 14 ) rest with a resilient clamping force against the upper face and the lower face of the holding region ( 8 ). The profiled limb ( 14 ), which in the clamped state rests against the lower face of the holding region ( 8 ) facing the supporting structure, forms a fixing surface ( 26 ) on the outer face thereof, which is provided with a connecting element ( 30 ) for attaching to the supporting structure.

The invention relates to a device for fastening panel-form mats, in particular flexible photovoltaic solar panels, to a supporting structure.

In the course of the advancing development of solar cells, solar energy recovery has expanded into a plurality of applications. Thus solar panels are attached to roofs or facades not only for stationary energy recovery for supply of buildings or are set up on corresponding usable surfaces, but also are used on a mobile basis in the form of mat-like, flexible solar panels which are also referred to as thin film solar panels. Such flexible solar panels are attached, for example, to exterior surfaces, especially roof surfaces, of motor vehicles, sporting goods, or recreational gear, and to sport aircraft such as gliders, in order to form a self-contained power supply or to support one. In addition to a plurality of other possible applications, as a result of their flexibility, mat-like solar panels are also suitable for attachment to certain types of functional clothing, for example, in safety clothing for the supply of integrated telemetry devices or communications devices.

The fastening to pertinent supporting structures becomes difficult in view of the mechanical properties of flexible solar panels. The flexibility of the panels does facilitate the attachment to carrier surfaces which are not flat, as is generally the case in parts of motor vehicle bodies, but also often in other equipment. Document WO 2007/123927 A2, in this respect, discloses a solution in which, on the entire lower face of the mat-like structure, an adhesive connection to the adjoining supporting structure is formed. This solution is not entirely satisfactory in that the surface of the supporting structure must be suitable for forming the large-area adhesive connection and because major temperature changes, as can occur with high temperature values, for example, on vehicle bodies, can lead to distortions or warping due to different coefficients of thermal expansion.

With respect to this problem, the object of the invention is to provide a device which enables a simple, economical, and reliable fastening of panel-like mats, such as flexible solar panels.

According to the invention, this object is achieved by a device having the features specified in claim 1 in its entirety.

Accordingly, the invention provides for there to be plastic clamping clips which have the shape of sections of a plastic profiled body, with profiled limbs opposite one another forming between themselves a clamping space in order to clamp between themselves a holding region of a pertinent mat or of a solar panel with a resilient clamping force. The clamping clips for their part, for attachment to the supporting structure, have a fastening surface on the outside of the profiled limb which in the clamping state adjoins the lower face of the clamped holding region, there being a connecting element between fastening surface and supporting structure. The use of clamping clips forms nonpositive anchoring in which relative movements are possible between the panel and the fastening points formed by the clamping regions of the clamping clips so that thermal expansions of the supporting structures can be compensated and stresses and cracks can thus be avoided. The device is characterized by low installation effort and is moreover extremely economical since large-area connecting elements which extend over the entire lower face of the panel are not necessary.

In especially advantageous exemplary embodiments, a touch-and-close fastener part is attached to the fastening surface of the lower profiled limb as the connecting element, and the interlocking elements of the part form an adhesive connection to interlocking elements located on the supporting structure. Such a touch-and-close fastener part can have conventional interlocking elements in the form of mushroom heads, loops, or hooks. For interlocking elements in the form of hooks, the clamping clips can be fastened especially advantageously to textile or fleece-like supporting structures, with the textile structure or the fleece itself forming the interlocking elements on the support structure. The interlocking elements which belong to the clamping clip can be provided on a separate touch-and-close fastener part whose backing is bonded or cemented to the fastening surface of the pertinent profiled limb. Alternatively, especially interlocking elements made like mushroom heads can also be formed on the fastening surface from the material of the profiled limb itself.

Advantageously, clamping clips with elongated profiled limbs can be provided in the form of flat tapes, of which the limb adjoining the lower face of the holding region of a pertinent mat is longer than the upper limb. While a desired, sufficient clamping force can thus be achieved by a profiled limb of comparatively shorter length, on the other correspondingly longer profiled limb, a fastening surface is available with the desired surface size.

The arrangement can advantageously be made such that the lower limb has the shape of a flat tape and on the inside forms a flat clamping surface for the holding region of a solar panel and on the outside has a flat fastening surface which accommodates the connecting element.

With respect to the shape of the upper profiled limb, in its starting region it can advantageously run flat corresponding to the lower limb, and in its middle longitudinal region it can undergo transition into an arch which approaches the lower limb such that in the vicinity of the free end an arched clamping surface is formed, after which the arch toward the free end begins to transition away from the lower limb. Shaping of this type facilitates slipping of the clamping clips onto the holding regions of the pertinent panel due to the end region of the upper profiled limb, which region is arched to the outside, with the clamping force acting at the same time with high surface pressure on the holding region due to the arched clamping surface which has been formed.

When using the device for a solar panel in which holding regions are formed by edge zones which have a smaller thickness than the solar modules located within the edge zones, the profiled limbs of the clamping clips can be joined to one another via a profiled web whose length is less than the solar panel height formed from the thicknesses of the solar modules and edge zones. The clamping clips thus have the shape of flat clamps which in the clamping state do not form any elevation at all which projects over the upper face of the solar modules.

Especially advantageously, the profiled body of the clamping clips can be formed from a thermoplastic, easily cementable polymer, for example, acrylonitrile-butadiene-styrene (ABS).

In view of the fact that the clamping clips are exposed during use in a device for fastening of solar panels, at least the part of the clamping clip which is exposed in the clamped state is preferably provided on the outside with a sunproof and weatherproof coating such as polymethyl methacrylate (PMMA).

The invention is detailed below using one exemplary embodiment which is shown in the drawings.

FIG. 1 shows a highly simplified perspective oblique view of the upper face of a solar panel, only on two edge zones which lie outside the solar modules, there being a clamping clip according to one exemplary embodiment of the device according to the invention;

FIG. 2 shows a side view of an individual clamping clip, which view is shown slightly enlarged compared to a practical embodiment, according to the exemplary embodiment of the invention, and

FIG. 3 shows a partial section according to the cutting line III-III from FIG. 2, which section is shown on the scale according to FIG. 2.

The invention is explained below using the example of the fastening of a mat-like flexible solar panel. It goes without saying that the invention is equally well suited to fastening other types of panel-like mats. The solar panel, which is designated as a whole as 2 in FIG. 1, on support sheeting 4, which is fabricated from a preferably burled plastic sheet with a rectangular outline, has an arrangement consisting of a plurality of solar modules, of which in FIG. 1 only a few rows are designated as 6. In commercial solar modules 2 of this type, the sheeting 4 has dimensions of roughly 55×40 cm and consists of a weatherproof plastic material such as PMMA or PTFE. The solar modules 6 are arranged on the sheeting 4 such that edge zones 8 which remain exposed along the four sides are formed. In the present example, these edge zones 8 are used as holding regions in order to anchor the solar panel 2 on a supporting structure, which is not shown in the figures, in interaction with clamping clips 10 of the device according to the invention. In FIG. 1, only two clamping clips 10 on oppositely facing side edges are illustrated. In the practical application, a suitable plurality of other clamping clips 10 can act on other regions of the edge zones 8, for example, on the other corner regions. In a material of the clamping clips 10 which is translucent to solar radiation, said clips can also be easily located on the solar panel 2 overlapping the region of the solar modules 6.

FIGS. 2 and 3 show details of the clamping clips 10. These are one-piece profiled bodies of a thermoplastic with elasticity properties that are suitable for producing a clamping force, and it can preferably be an easily cementable polymer such as acrylonitrile-butadiene-styrene (ABS). Such a profiled body can be efficiently formed by a corresponding strand profile being extruded and by sections which form the individual clamping bodies 10 being cut off the strand. FIGS. 2 and 3 show the profiled shape of the profiled body with two elongated profiled limbs 12 and 14 in the form of flat tapes which are flush with one another, which are opposite one another and of which the profiled limb 14 which is at the bottom in the figures is longer than the upper profiled limb 12. The profiled limbs 12, 14 are joined to one another via a profiled web 16 whose length is dimensioned such that between the limbs 12, 14, a clamping space 18 is formed in which the edge zone 8 of the solar panel 2 which is used as a holding region can be accommodated. However, the clamping clip 10 in the clamping state shown in FIG. 3 does not project above the upper face of the solar modules 6.

FIG. 3 shows the clamping state in which the edge zone 8 with its lower face adjoins the inner face of the lower profiled limb 14 and the upper profiled limb 12 which is deflected upward compared to the state shown in FIG. 2 against the force of its elasticity and adjoins the upper face of the edge zone in order to apply a clamping force between itself and the lower profiled limb 14. As FIGS. 2 and 3 show, the upper limb 12 in its starting region runs flat corresponding to the lower limb 14, but in a middle longitudinal section undergoes transition into an arch toward the lower limb 14 and, in the vicinity of its free end 20, forms an arched clamping surface 22 which is connected toward the free end 20 to an opposite arch through which the free end 20 again transitions away from the lower profiled limb 14. This variation results in a widening of the entry region to the clamping space 18, as a result of which the mounting is simplified when the clamping clips 10 are attached.

In order to protect the parts of the clamping clips 10 which are exposed during use, there is a sunproof and weatherproof coating 24 which on the clamping clip 10, proceeding from the outer face of the profiled web 16, extends over the upper profiled web 12 and beyond its free end 20 into the vicinity of the clamping surface 22. For example, materials such as polymethyl methacrylate (PMMA) or polytetra-fluoroethylene (PTFE) are suitable for this coating 24. This coating 24 can be efficiently fabricated by a coextrusion method in the production of the profiled strand which forms the clamping clips 10.

The lower profiled limb 14 with its lower face forms the fastening surface 26 for anchoring on the supporting structure (not shown). In FIG. 3, there is a connecting element which is designated as 30 between longitudinal ribs 28 on the connecting surface 26. To form an adhesive connection to the supporting structure, the connecting element 30 can be a layer of adhesive. Advantageously, however, the connecting element 30 can be a touch-and-close fastener part which is cemented or bonded to the fastening surface 26. It can be a touch-and-close fastener part of a type suitable for the respective application and can be interlocked in a suitable manner with its interlocking elements to the assigned interlocking elements located on the supporting structure. Interlocking elements in the shape of mushroom heads, hooks, or loops are possible, depending on the circumstances on the supporting structure. If the surface of the supporting structure is a textile or fleece-like material, hook-shaped interlocking elements can be preferably provided and can be directly interlocked with the fleece material or the textile structure. However, alternatively, there can also be interlocking elements shaped like mushroom heads, which elements are molded directly on the lower profiled limb 14 in order to interact with a plastic touch-and-close fastener part which is located on the supporting structure.

It is preferably provided that the fastening device according to the invention is not formed as an individual clamp body, but rather extends over the entire length and/or width of a photovoltaic solar panel so that, together with the respective solar panel, a complete fastening system is obtained in which the respective panel, viewed in the direction of looking at FIGS. 2 and 3, can be pushed in with its outer edge perpendicular to the plane of the drawing. In this way, the respective fastening device which is then made in the shape of a strip with any definable length can remain adhering to the base structure, and a replacement of the respective panel at any time is possible, for example, when the photovoltaic components of the solar panel 2 are worn.

To the extent coating is addressed in this invention, it can be produced by application coating, or within the framework of an extrusion method, or the like, it can form a cover layer. Instead of polytetrafluoroethylene, other polyfluoropolymers can also be used. 

1. A device for fastening panel-form mats, in particular flexible photovoltaic solar panels (2), to a supporting structure, having at least one clamping clip (10) in the form of a section of a plastic profiled body which has profiled limbs (12, 14) which are opposite one another and which between themselves form a clamping space (18) for a holding region (8) of the pertinent mat, which region is held in the clamping space and in which the profiled limbs (12, 14) with a resilient clamping force adjoin the upper face and the lower face of the holding region (8), wherein the profiled limb (14), which in the clamping state adjoins the lower face of the holding region (8) facing the supporting structure, on its outer face forms a fastening surface (26) which is provided with a connecting element (30) for attachment to the supporting structure.
 2. The device according to claim 1, characterized in that there are clamping clips (10) with elongated profiled limbs (12, 14) in the form of flat tapes, of which the lower limb (14) which adjoins the lower face of the holding region (8) of a pertinent mat is longer than the upper limb (12).
 3. The device according to claim 2, characterized in that the lower limb (14) has the shape of a flat tape and on the inside forms a flat clamping surface (22) for the holding region (8) of one of the solar panels (2) and on the outside forms a flat fastening surface (26) which holds the connecting element (30).
 4. The device according to claim 3, characterized in that the upper limb (12) in its starting region runs flat corresponding to the lower limb (14) and in its middle longitudinal region undergoes transition into an arch which approaches the lower limb (12) such that in the vicinity of the free end (20) an arched clamping surface (22) is formed, after which the arch toward the free end (20) begins to transition away from the lower limb (14).
 5. The device according to claim 1, characterized in that for a solar panel (2) in which holding regions are formed by edge zones (8) which have a smaller thickness than the solar modules (6) located within the edge zones (8), the profiled limbs (12, 14) of the clamping clips (10) are joined to one another via a profiled web (16) whose length is less than the height of the solar panel (6), which height is formed from the thicknesses of the solar modules (6) and edge zones (8).
 6. The device according to claim 1, characterized in that the profiled body of the clamping clips (10) is formed from a thermoplastic, easily cementable polymer, for example, acrylonitrile-butadiene-styrene (ABS).
 7. The device according to claim 1, characterized in that at least the part of the clamping clip (10) which is exposed in the clamped state is provided on the outside with a sunproof and weatherproof coating (24), for example, of polymethyl methacrylate (PMMA).
 8. The device according to claim 1, characterized in that as the connecting element (30) a touch-and-close fastener part is attached to the fastening surface (26) of the lower profiled limb (14) and the interlocking elements of the touch-and-close fastener part form an adhesive connection to interlocking elements located on the supporting structure. 